Continuous measurements of microcirculatory blood flow in gastrointestinal organs during acute haemorrhage

Abstract

Hypoperfusion of splanchnic organs is an important contributor to the development of multiple organ failure after major surgery and trauma. During general anaesthesia and surgery we compared changes in systemic haemodynamics and regional blood flow with changes in the distribution of microcirculatory flow (MBF) in multiple splanchnic organs in pigs exposed to acute haemorrhage. Seven pigs (25 kg) were bled to a mean arterial pressure of 40 mm Hg; 180 min later the shed blood was retransfused. MBF was measured in the intestinal mucosa (stomach, jejunum, colon), pancreas, liver and kidney using a six-channel laser Doppler flowmeter. Cardiac output was measured by thermodilution and superior mesenteric artery flow by ultrasonic flowmetry. During haemorrhage, MBF in the gastric and colon mucosa and flow in the liver and kidney decreased to a similar extent to regional and systemic flows (30-50%). In contrast, MBF in the jejunal mucosa remained virtually unchanged and flow in the pancreas decreased significantly more than systemic and regional flows (60%, PϽ0.05). We conclude that: (1) changes in the distribution of MBF in the gastrointestinal tract during acute haemorrhage are heterogeneous and cannot be predicted from changes in systemic or regional haemodynamics; (2) MBF in the jejunal mucosa did not decrease during haemorrhage, indicating that autoregulation of blood flow in the mucosa remained intact during shock; and (3) MBF in the pancreas decreased significantly more than systemic and regional flows during shock, suggesting that the pancreas is particularly vulnerable to haemorrhage. 2000; 84: 468-75 Br J Anaesth

Jejunal luminal microdialysate lactate in cardiac tamponade – effect of low systemic blood flow on gut mucosa

“…Cardiac tamponade per se increases sympathetic tone [34]. In addition, jejunal mucosal blood flow, when estimated by laser Doppler flowmetry, is preserved while systemic and regional blood flow decreases in an experimental hemorrhagic shock [35]. Furthermore, arterial hypotension during regional flow reduction redistributes blood flow towards the mucosa [14].…”

Non-Invasive Characterization of Oxygen Transport in Sickle Cell Disease: A Pilot Study

“…The introduction of regional measurement techniques has highlighted the inadequacy of the information being garnered by global measurements of hemodynamic oxygenation such as DO 2 , VO 2 , and arterial hemoglobin oxygen saturation as well as traditional physical examination findings such as blood pressure and heart rate. Therefore, consideration should be given to emphasizing the underlying microcirculation, 26,27 as reflected in tissue oxygenation as both a diagnostic and therapeutic endpoint.…”

Experimental study of state of gastric mucosa in rats under introduction of new derivate of 4-[4-oxo-4h-quinazoline-3-yl] benzoic acid (PC-66)

“…In addition, PGE1 boosts formation of gastric mucosa glycoproteins, namely, N-acetylneuraminic acid and bicarbonates, thus providing GM protective properties and improving microcirculation in the gastric wall. Patients with erosive changes in gastric mucosa always presented reduced levels of PGE and PGE1 [16].…”